Ischemic heart disease causes mitral regurgitation by the combination of ischemic dysfunction of the papillary muscles, and the dilatation of the left ventricle that is present in ischemic heart disease, with the subsequent displacement of the papillary muscles and the dilatation of the mitral valve annulus.
Dilation of the annulus of the mitral valve prevents the valve leaflets from fully coapting when the valve is closed. Mitral regurgitation of blood from the left ventricle into the left atrium results in increased total stroke volume and decreased cardiac output, and ultimate weakening of the left ventricle secondary to a volume overload and a pressure overload of the left atrium.
US Patent Application Publications 2004/0260393 to Rahdert et al. and 2004/0127982 to Machold et al. describe techniques using an implant that is sized and configured to attach in, on, or near the annulus of a dysfunctional heart valve. In use, the implant extends either across the minor axis of the annulus, or across the major axis of the annulus, or both. The implant is described as restoring to the heart valve annulus and leaflets a more functional anatomic shape and tension. The more functional anatomic shape and tension are conducive to coaptation of the leaflets, which, in turn, reduces retrograde flow or regurgitation. In some embodiments, the implant is configured to rest at or near a heart valve annulus and apply a direct mechanical force along the minor axis of the annulus to inwardly displace tissue toward the center of the annulus. For some applications, the implant is configured to extend significantly above the plane of the valve, while for other applications, the implant is configured to extend a short distance above the plane of the valve.
U.S. Pat. No. 7,500,989 to Solem et al. describes devices and methods for treating mitral regurgitation by reshaping the mitral annulus in a heart. One device for reshaping the mitral annulus is provided as an elongate body having dimensions as to be insertable into a coronary sinus. The elongate body includes a proximal frame having a proximal anchor and a distal frame having a distal anchor. A ratcheting strip is attached to the distal frame and an accepting member is attached to the proximal frame, wherein the accepting member is adapted for engagement with the ratcheting strip. An actuating member is provided for pulling the ratcheting strip relative to the proximal anchor after deployment in the coronary sinus. In one embodiment, the ratcheting strip is pulled through the proximal anchor for pulling the proximal and distal anchors together, thereby reshaping the mitral annulus.
The following patents and patent applications may be of interest:
EP Patent EP 06/14342 to Pavcnik et al.
EP Patent EP 10/06905 to Organ
PCT Publication WO 00/22981 to Cookston et al.
PCT Publication WO 01/26586 to Seguin
PCT Publication WO 01/56457 to Pruitt
PCT Publication WO 05/046488 to Douk et al.
PCT Publication WO 06/012013 to Rhee et al.
PCT Publication WO 06/086434 to Powell et al.
PCT Publication WO 06/097931 to Gross et al.
PCT Publication WO 06/105084 to Cartledge et al.
PCT Publication WO 96/39963 to Abela et al.
PCT Publication WO 96/40344 to Stevens-Wright et al.
PCT Publication WO 97/01369 to Taylor et al.
PCT Publication WO 98/46149 to Organ
U.S. Pat. No. 3,656,185 to Carpentier
U.S. Pat. No. 4,961,738 to Mackin
U.S. Pat. No. 5,325,845 to Adair
U.S. Pat. No. 5,593,424 to Northrup III
U.S. Pat. No. 5,716,370 to Williamson, IV et al.
U.S. Pat. No. 5,855,614 to Stevens et al.
U.S. Pat. No. 6,074,401 to Gardiner et al.
U.S. Pat. No. 6,102,945 to Campbell
U.S. Pat. No. 6,619,291 to Hlavka et al.
U.S. Pat. No. 6,918,917 to Nguyen et al.
U.S. Pat. No. 6,926,730 to Nguyen et al.
U.S. Pat. No. 7,150,737 to Purdy et al.
U.S. Pat. No. 7,172,625 to Shu et al.
U.S. Pat. No. 7,175,660 to Cartledge et al.
U.S. Pat. No. 7,226,467 to Lucatero et al.
US Patent Application Publication 2003/0078465 to Pai et al.
US Patent Application Publication 2003/0199974 to Lee et al.
US Patent Application Publication 2004/0127983 to Mortier et al.
US Patent Application Publication 2004/0148021 to Cartledge et al.
US Patent Application Publication 2004/0260394 to Douk et al.
US Patent Application Publication 2005/0055038 to Kelleher et al.
US Patent Application Publication 2005/0096740 to Langberg et al.
US Patent Application Publication 2006/0095009 to Lampropoulos et al.
US Patent Application Publication 2006/0195134 to Crittenden
US Patent Application Publication 2006/0282161 to Huynh et al.
US Patent Application Publication 2006/0247763 to Slater
US Patent Application Publication 2008/0027483 to Cartledge et al.
US Patent Application Publications 2004/0148019 and 2004/0148020 to Vidlund et al.
The following articles, which are incorporated herein by reference, may be of interest:
O'Reilly S et al., “Heart valve surgery pushes the envelope,” Medtech Insight 8(3): 73, 99-108 (2006)
Dieter R S, “Percutaneous valve repair: Update on mitral regurgitation and endovascular approaches to the mitral valve,” Applications in Imaging, Cardiac Interventions, Supported by an educational grant from Amersham Health pp. 11-14 (2003)
Swain C P et al., “An endoscopically deliverable tissue-transfixing device for securing biosensors in the gastrointestinal tract,” Gastrointestinal Endoscopy 40(6): 730-734 (1994)
Odell J A et al., “Early Results of a Simplified Method of Mitral Valve Annuloplasty,” Circulation 92:150-154 (1995)